According to actual lore protoframes are just random people that were arbitrarily given a particular warframe's helminth strain. The original warframes might have conceivably taken on traits of their first host, putting their identity onto the strain, but that's not what protoframes are. (The latter would have been the more interesting kind of "protoframe" to see.)
Nonetheless Father Lyon Allard seems to have coincidentally been the human version of Harrow already. Get ready for a retcon making protos the origin frames.